SOFIA: First Light

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a next- generation airborne observatory designed to provide astronomers routine access to the infrared and sub-millimeter part of the electromagnetic spectrum. SOFIA was initiated by NASA’s Science and Mission Directorate as an integral element of an overall strategy to obtain data to better understand the nature and evolution of the universe, the origin and evolution of galaxies, stars, and planetary systems, and the conditions which led to the origins of life. The SOFIA program is a joint effort between the National Aeronautics and Space Administration (NASA) and the Deutsches Zentrum für Luftund Raumfahrt (DRL), the German Space Agency.

On May 26, 2010 the SOFIA Program achieved a major milestone with its first in-flight night observations. The highly modified SOFIA Boeing 747SP fitted with a 2.5 m diameter reflecting telescope took off from its home base at the Dryden Aircraft Operations Facility (DAOF) in Palmdale, California at sunset on May 25, 2010. In-flight personnel consisted of an international crew from NASA, the Universities Space Research Association (USRA) in Columbia, Md., Cornell University and the German SOFIA Institute (DSI) in Stuttgart. During the six-hour flight, at altitudes up to 35,000 feet, the crew of 10 scientists, astronomers, engineers and technicians gathered telescope performance data at consoles in SOFIA’s main cabin. The goal of the SOFIA First Light Flight was to characterize the performance of the German- made telescope and integrate the telescope’s systems/subsystems with the first flown science instrument. “First Light” is a term astronomers use to describe the first viewing with a new telescope. SOFIA returned to the NASA DAOF at approximately 5:30 A.M. on May 26th with an ecstatic mission crew and it first images captured by the telescope and USRA’s Cornell University’s FORCAST science instrument.

SOFIA evaluates Jupiter in infrared using its first flown science instrument, FORCAST.

The stability and precise pointing of the German built telescope met and exceeded the expectations of the engineers and astronomers who put it through its paces during the flight. The main accomplishment of the night occurred when scientists on board SOFIA recorded images of Jupiter and the M82 galaxy in the Ursa Major constellation using FORCAST. The Faint Object Infrared Camera (FORCAST) is a mid-infrared diffraction-limited camera with selectable filters for simultaneous continuum imaging in two bands, within the 4-25 and 25-40 μm spectral regions. The composite infrared image of Jupiter, illustrated in Figure 1.1, at wavelengths of 5.4 (blue), 24 (green) and 37 microns (red) shows heat trapped since the formation of the planet, pouring out of Jupiter’s interior through holes in its clouds.

FORCAST captured in minutes images that would require many hour-long exposures by ground-based observatories blocked from a clear infrared view by water vapor in the Earth’s atmosphere. The SOFIA’s operational altitude, which is above more than 99 percent of that water vapor, allows it to receive 80 percent or more the infrared light accessible to space observatories.

The success of the First Light Flight begins SOFIA on a 20-year journey that will enable a wide variety of astronomical science observatories not possible from ground-based observatories and it also proves SOFIA will provide scientists with Great Observatory-class astronomical science.

The SOFIA program is managed at the NASA Dryden Flight Research Center. The NASA Ames Research Center manages the SOFIA science and mission operations in cooperation with USRA and DSI.